<?php
/**
 * Created by PhpStorm.
 * User: dfh
 * Date: 2016/9/28
 * Time: 14:45
 */
header('Content-type:text/html;charset=utf-8');
$name='小明';
$score=78;
if(is_int($score)||is_float($score)){
  if($score>=90 && $score<=100)  {
      $str ='A级';
  }elseif ($score>=70 &&  $score<=90){
      $str='B级';
  }elseif ($score>=60 && $score<=70){
      $str='C级';
  }elseif ($score>=50 && $score<=60){
      $str='D级';
  }elseif ($score>=0 && $score<=60){
      $str='E级';
  }else {
      $str = '学生成绩必须在0~100！';
  }
}
else{
        $str='输入的学生成绩不是数值!';
    }
echo "<h2>学生成绩等级</h2><p>学生姓名:".$name."<p>学生分数:".$score."分<p>成绩等级：".$str;